Is the system tough? Does it build toughness instead? Or is it a way for people to claim some sort of bragging rights? "I do system X, and that makes me a bad MoFo." Like the guys I constantly see wearing Tapout or some other MMA gear. The majority want to be associated with that reputation, and have some of it rub off on them.
Is the material I teach hard to learn, in that sense of tough? No, I don't think so. The majority is what I've learned from Hock and Guru Hallock, along with my own experiences in various TMA and real life encounters.
Do I think that the material and my teaching method build tougness? In the sense that I believe it builds tenacity, yes. From my friend who now lives in Vegas who was once afraid to punch me, and eventually ended up leaving a few knots on my head and a bite mark on my ribs. She once jacked a dude up in a bar with a rear armbar hammerlock for putting a hand on her after she told him not to. I don't say this because I taught her everything. I facilitated it. When I teach someone something, what I do is facilitate them finding a new strength or ability they didn't realize they had. Whether it's FMA, a new lift, or better technique in the shotput.
As for walking around with my head high, a chip on my shoulder, or just generally thinking I'm tough? Absolutely I do. I know when there's no one around who could stop me from teaching some punk a lesson. People, especially in the Guard, have gotten in my face, and started fights with me, or at least threatened. I know that when it drops in the pot in a situation like that, I'm going to come out on top 95% of the time, because of training, dedication, ability, and just plain meanness. These are the things I attempt to pass on to other people. Some are more dedicated, some less. Some have more natural ability, some less. Some have to work a little more to get in touch with their inner Hulk.
When I'm evaluating someone, which is pretty much all the time, I don't look for perfect technique. Instead, I look for understanding of the technique, and curiosity about it. There will generally be time to refine the technique to the point of perfection. In a fight, I'm more concerned that whoever I've taught be able to inflict more damage than they receive, in a responsible manner. In addition, I'm usually evaluating morals and ethics. I've known more than a few people who had some time in FMA that I would never consider teaching or training with. Potheads, mainly, around here.
I'm not certain that toughness really needs to exist in most systems that are well grounded in reality and common sense. Mental toughness and physical readiness are both byproducts of training, whether from sparring, statue drills, forms, or calisthenics. If there is a system that is focused on some definition of "toughness", it's safe to say that it's probably a very small niche.
Kent